(i) Field to which the invention relates
The invention relates to a handle of round tube for home utensils, more specially brooms, with a threaded sleeve, whose conical threaded hollow male endpiece is screwed into the utensil, for example a broom head, and on the inside is made uneven for locking onto the handle end.
(ii) The prior art
Handles for home utensils, made of steel or aluminum tube, are used in a great number of different forms and for different purposes. Threaded sleeves used in this respect for screwing the handle in position generally have a cylindrical or hollow conical endpiece, in which the cylindrical handle, or its conical endpiece, is simply forced and kept in position by friction. In the case of such male threaded sleeves of synthetic resin or metal, the utensil handle is not generally locked or gripped in position strongly enough and it is quite likely for the broom head to become loose and be dropped off on sweeping.
For making a better form of this connection there has been a suggestion (see German Pat. No. 2,330,165) to make the endpiece of great length and for it to be wedged on the tube by using a male conical element. Such a wedging operation is, however, only possible in the case of a welded or seamless tube. Furthermore, on driving the conical element into the tube, the last-named is bent and becomes unsightly. In the case of other fixing systems, a synthetic resin or metal male threaded sleeve is united with the steel or aluminum handle by nailing using staple nails, which, however, are quite likely to become loose and on shaking may come out of the handle completely.
In a further design on these general lines (see the German Gebrauchsmuster Pat. No. 7,503,826), the hollow conical endpiece of the handle has asymmetrical, pressed-in grooves for taking up opposite ridges of the male threaded sleeve. After pushing the handle into position, the grooves are forced up against the ridges, this stopping any twisting of the handle. Furthermore, from the open end, a plug is forced into the threaded sleeve, the plug having an uneven form for producing a locking effect. A shortcoming in this design is the great number of separate parts, the need to keep to certain, narrow tolerances between the tube handle and the threaded sleeve and the need for carefully putting the threaded sleeve and handle in line with each other on fixing them together.